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Message-ID: <ccbd7330-b7d7-9048-b49a-80f904353c21@redhat.com>
Date:   Thu, 5 Jan 2023 10:04:14 +0100
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Subject: Re: [PATCH v2 1/1] mm: fix vma->anon_name memory leak for anonymous
 shmem VMAs
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To:     Suren Baghdasaryan <surenb@google.com>, akpm@linux-foundation.org
Cc:     hughd@google.com, hannes@cmpxchg.org, vincent.whitchurch@axis.com,
        seanjc@google.com, rppt@kernel.org, shy828301@gmail.com,
        pasha.tatashin@soleen.com, paul.gortmaker@windriver.com,
        peterx@redhat.com, vbabka@suse.cz, Liam.Howlett@Oracle.com,
        ccross@google.com, willy@infradead.org, arnd@arndb.de,
        cgel.zte@gmail.com, yuzhao@google.com, bagasdotme@gmail.com,
        suleiman@google.com, steven@liquorix.net, heftig@archlinux.org,
        cuigaosheng1@huawei.com, kirill@shutemov.name,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-mm@kvack.org,
        syzbot+91edf9178386a07d06a7@syzkaller.appspotmail.com
References: <20230105000241.1450843-1-surenb@google.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20230105000241.1450843-1-surenb@google.com>
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On 05.01.23 01:02, Suren Baghdasaryan wrote:
> free_anon_vma_name() is missing a check for anonymous shmem VMA which
> leads to a memory leak due to refcount not being dropped.  Fix this by
> calling anon_vma_name_put() unconditionally. It will free vma->anon_name
> whenever it's non-NULL.
> 
> Fixes: d09e8ca6cb93 ("mm: anonymous shared memory naming")
> Signed-off-by: Suren Baghdasaryan <surenb@google.com>
> Suggested-by: David Hildenbrand <david@redhat.com>
> Reported-by: syzbot+91edf9178386a07d06a7@syzkaller.appspotmail.com
> Cc: David Hildenbrand <david@redhat.com>
> Cc: Hugh Dickins <hughd@google.com>
> Cc: Pasha Tatashin <pasha.tatashin@soleen.com>


Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Thanks,

David / dhildenb